Every minerals processing operation produces a tailings stream, which invariably contains valuable metals that were not recovered during processing. Often this represents very low concentrations of the target metal and safe storage of the tailings is the best solution. However, there are cases where metals end up in the tailings stream in concentrations that are economically recoverable. This may be due to inefficient processing or may be a by-product that was not the target of primary processing. In these cases it may be valuable to investigate reprocessing of the tailings to recover those metals.
For historic operations processing may not have been as efficient, resulting in more value contained in the tailings facility. There are also often legacy environmental issues that may be addressed if the tailings are reprocessed.
MinAssist specialises in evaluation of opportunities for value generation from minerals processing tailings and mine waste.
We have evaluated over 50 tailings facilities globally and have developed processes for rapid determination of whether an economically viable reprocessing project could be undertaken.
Processing of tailings is complex and requires innovative approaches to flow sheet development. Valuable minerals were generally not recovered during primary processing for a good reason and often this complexity is further compounded by oxidation of the mineral surfaces while in the tailings dam. Operations need to be highly capital efficient and achieve rapid payback. In addition, the process should aim to also remove negative environmental legacy components, ensuring the final waste stream is benign and can be safely and permanently disposed of. MinAssist has experience in all these aspects of tailings reprocessing project development.
- Tailings value evaluation and financial modelling
- Tailings reprocessing process flow sheet development
MinAssist has completed a number of significant tailings projects:
MinAssist undertook detailed mineral characterisation for Cleveland tailings material and fresh ore for Elementos Ltd. The grain size of cassiterite in the Cleveland tailings is very fine, often less than 15 micron, requiring a different processing configuration to a conventional tin gravity circuit. Working with Elementos MinAssist developed a process flow sheet focusing on fine cassiterite recovery using a combination of flotation and fine gravity separation.
MinAssist, with Rodinia Resources Pty Ltd has developed technology for biorehabilitation of bauxite waste (Red Mud). This process converts the hazardous Red Mud to an engineered soil (Technosol) that is suitable for use in agriculture or mine rehabilitation. In addition, the process produces a feedstock that is suitable for extraction of residual metal value, in this case scandium and gallium.
How can we help you?
- Characterisation of contained value and legacy environmental impacts of tailings dams
- Development of a capital efficient process for recovery of value from tailings